Cancer rates rising in under-50s

Cancer rates in 25 to 49-year-olds in the UK increased by 24% between 1995 and 2019, according to our latest analysis.

Around 9 in 10 cancer cases still happen in people over 50, but early-onset cancers are a growing cause for concern. Approximately 100 younger adults in the UK were diagnosed with cancer every day between 2017 and 2019.

The increase in the number of cancer cases in this age group is still relatively small and is partially explained by population growth and improvements in diagnosis. Still, the percentage change is more than twice the 10% rise in over-75s, the group most at risk of the disease.

“Over recent decades, there has been a clear increase in cancer incidence rates in young adults in the UK,” said Professor Charles Swanton, our chief clinician. “Evidence suggests that more adults under 50 may be getting cancer than ever before.”

Almost 35,000 people aged between 25 and 49 were diagnosed with cancer in 2019. Incidence rates in this age group grew from 132.9 per 100,000 people in 1995 to 164.6 in 2019.

The number of new cases in over-75s grew from 2,259.7 per 100,000 people to 2,482.7 per 100,000 over the same period.

“Changes to lifestyles and diets over time, and rising obesity, may all contribute to the uptick in early-onset cancer,” said Swanton. “Genetics, improvements in diagnosis and screening and the microbiome could also play a role.”

“It really is a scientific conundrum that urgently needs to be solved.”

Team PROSPECT, who we recently funded through Cancer Grand Challenges, are working on the problem. One of PROSPECT’s researchers, Dr Aparna Parikh, a professor of medicine at Harvard medical school and an oncologist at Massachusetts general hospital, talked through the team’s plan at the American Society for Clinical Oncology annual meeting over the weekend.

“We want to gain a deep mechanistic understanding of biological processes and environmental causes, and to do this we’re looking at a diverse set of data and patients from all around the world,” Parikh explained.

“This is complex, and the rise in early-onset colorectal cancer cases is driven by various factors, including diet, the environment, and features of the microbiome. A greater understanding of why cancer cases are rising can help us understand how to intervene and identify high risk patients for cancer screening. By trialling methods to assess risk and prevent early-onset colorectal cancers, we can shape a hopeful and healthier future for younger generations.”

PROSPECT’s approach is informed by all the research scientists have already done into preventable cancer risk factors.

“Around four in 10 cancer cases are preventable, and there are steps people can take to help reduce their cancer risk,” Swanton said. “Not smoking, keeping a healthy weight, being safe in the sun and cutting down on alcohol all make a big difference.”

You can find out more about reducing cancer risk on our Causes of Cancer pages.